1320london

First off I apologize for all the stupid questions I'm really new to this. Ok so I have some h beam forged rods not sure of brand but for b16. I just bought a set of NPR pistons with rings and pins.when I bought them I thought u had to have the pins preesed but when I was messing with them I got a pin to go all the way thru. My question is since there's no locks and they slide with ease how do they stay in place.

jalenda9

Welcome man and I have npr pistons as well. Mines were floating wrist pins but I got them in a package deal with forged scat rods. I was able to push mines in but not by hand. I just took a mallet and lightly tapped them with a rag over the pin and put the spiral clips in place. Look at the listing or wherever you got them from and check the item description to see if they are floating or press fit.

You don't want them too loose or too tight, the piston should be able to rock back in forth on the rod after installed

Edit: once you have them installed there should be small little clips called Spiro clips the basically have to be worked into the bore of the piston and at the very edge once you have the pins installed there should be a notch for the clip to sit in. This is what retains the pin and keeps it from falling out

jalenda9

Sorry for double post but here's a picture of the notch that should be at the edge of the wrist pin bore on the piston.
The black thing is a spiro clip

1320london

Mine isn't like that it looks flush and the kit doesn't have any spiral clips in it that's why I'm so confused

1320london

i cross refrenced the part number and couldnt find anything specific on what type they are, i bought them off ebay NIB, but here are some pics

jalenda9

That's really weird man....try taking it to a machine shop and ask them what they think

TomCat39

I suspect you got pressed pin style pistons while you got the bronze or is it brass bushing rods meant for floating pin.

Another words, your pistons don't match the rods and are expected to be put on stock rods that are press fit pins.

I would talk to NPR and see if you can exchange them for floating pin pistons.